TECHNICAL PROBLEMS POSED BY THE PRIOR ART
Some conventional mobile agricultural machines are provided with two or more frame sections or tool bars that are pivotally connected together with a conventional hinge assembly that permits one frame section to pivot or "float" relative to the other when the machine is being operated with the frame sections in a lowered, ground-engaging position on uneven terrain. This accommodates vertical variation in the terrain across the width of the machine.
When a laterally extending frame section of such a machine is raised away from the ground and folded back toward the adjacent section beyond a certain angle--as when the machine is being prepared for transport along a highway--the conventional hinge assembly permits the raised section to freely fall a short distance toward the other frame section. This "free fall" results in the machine being subjected to undesired impact loading.
It would be desirable to provide a folding implement frame section hinge assembly with an improved construction which, in addition to accommodating frame section float when a frame section is in the lowered, ground-engaging position, would permit a frame section to be smoothly raised and lowered. It would also be desirable if the improved hinge assembly could prevent free fall of a raised frame section during the folding and unfolding operations so as to avoid subjecting the machine to undesired impact loading.